US5701591A - Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception - Google Patents

Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception Download PDF

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Publication number
US5701591A
US5701591A US08/420,372 US42037295A US5701591A US 5701591 A US5701591 A US 5701591A US 42037295 A US42037295 A US 42037295A US 5701591 A US5701591 A US 5701591A
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channel
phase
rotating wave
wave
signal
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US08/420,372
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English (en)
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Thomas T. Y. Wong
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Telecommunications Equipment Corp
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Telecommunications Equipment Corp
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Priority to US08/420,372 priority Critical patent/US5701591A/en
Assigned to ILLINOIS INSTITUTE OF TECHNOLOGY reassignment ILLINOIS INSTITUTE OF TECHNOLOGY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Wong, Thomas T. Y.
Priority to US08/612,320 priority patent/US5764742A/en
Priority to UA97115395A priority patent/UA50736C2/uk
Priority to SK1359-97A priority patent/SK135997A3/sk
Priority to KR1019970707092A priority patent/KR19980703692A/ko
Priority to EP96912582A priority patent/EP0864209A1/en
Priority to CA002217686A priority patent/CA2217686C/en
Priority to EA199700309A priority patent/EA000444B1/ru
Priority to APAP/P/1997/001129A priority patent/AP895A/en
Priority to CN96193755A priority patent/CN1097363C/zh
Priority to CZ973162A priority patent/CZ316297A3/cs
Priority to NZ306724A priority patent/NZ306724A/xx
Priority to AU55355/96A priority patent/AU713294B2/en
Priority to BR9604936-7A priority patent/BR9604936A/pt
Priority to RO97-01849A priority patent/RO120442B1/ro
Priority to GEAP19963974A priority patent/GEP20012525B/en
Priority to JP8530496A priority patent/JPH11503292A/ja
Priority to EE9700260A priority patent/EE9700260A/xx
Priority to PCT/US1996/004694 priority patent/WO1996031957A1/en
Priority to HU9801986A priority patent/HU221392B1/hu
Priority to TR97/01124T priority patent/TR199701124T1/xx
Assigned to TELECOMMUNICATIONS EQUIPMENT CORPORATION reassignment TELECOMMUNICATIONS EQUIPMENT CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ILLINOIS INSTITUTE OF TECHNOLOGY
Priority to MXPA/A/1997/007733A priority patent/MXPA97007733A/xx
Priority to NO974638A priority patent/NO974638L/no
Priority to OA70100A priority patent/OA10623A/fr
Priority to US08/949,478 priority patent/US6006070A/en
Priority to BG102030A priority patent/BG102030A/xx
Priority to PL96322656A priority patent/PL180089B1/pl
Publication of US5701591A publication Critical patent/US5701591A/en
Application granted granted Critical
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Expired - Fee Related legal-status Critical Current

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/002Reducing depolarization effects
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q20/00Payment architectures, schemes or protocols
    • G06Q20/30Payment architectures, schemes or protocols characterised by the use of specific devices or networks
    • G06Q20/32Payment architectures, schemes or protocols characterised by the use of specific devices or networks using wireless devices
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q20/00Payment architectures, schemes or protocols
    • G06Q20/30Payment architectures, schemes or protocols characterised by the use of specific devices or networks
    • G06Q20/32Payment architectures, schemes or protocols characterised by the use of specific devices or networks using wireless devices
    • G06Q20/327Short range or proximity payments by means of M-devices
    • G06Q20/3272Short range or proximity payments by means of M-devices using an audio code
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q20/00Payment architectures, schemes or protocols
    • G06Q20/30Payment architectures, schemes or protocols characterised by the use of specific devices or networks
    • G06Q20/34Payment architectures, schemes or protocols characterised by the use of specific devices or networks using cards, e.g. integrated circuit [IC] cards or magnetic cards
    • G06Q20/346Cards serving only as information carrier of service
    • GPHYSICS
    • G07CHECKING-DEVICES
    • G07FCOIN-FREED OR LIKE APPARATUS
    • G07F7/00Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus
    • G07F7/08Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus by coded identity card or credit card or other personal identification means
    • G07F7/10Mechanisms actuated by objects other than coins to free or to actuate vending, hiring, coin or paper currency dispensing or refunding apparatus by coded identity card or credit card or other personal identification means together with a coded signal, e.g. in the form of personal identification information, like personal identification number [PIN] or biometric data
    • G07F7/1008Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00Antenna arrays or systems
    • H01Q21/24Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
    • H01Q21/245Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction provided with means for varying the polarisation 
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/015Reducing echo effects
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/02Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/10Polarisation diversity; Directional diversity
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/26Devices for calling a subscriber
    • H04M1/27Devices whereby a plurality of signals may be stored simultaneously
    • H04M1/274Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc
    • H04M1/2745Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips
    • H04M1/275Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips implemented by means of portable electronic directories
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/26Devices for calling a subscriber
    • H04M1/27Devices whereby a plurality of signals may be stored simultaneously
    • H04M1/274Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc
    • H04M1/2745Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips
    • H04M1/2753Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips providing data content
    • H04M1/2755Devices whereby a plurality of signals may be stored simultaneously with provision for storing more than one subscriber number at a time, e.g. using toothed disc using static electronic memories, e.g. chips providing data content by optical scanning
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/66Substation equipment, e.g. for use by subscribers with means for preventing unauthorised or fraudulent calling
    • H04M1/667Preventing unauthorised calls from a telephone set
    • H04M1/67Preventing unauthorised calls from a telephone set by electronic means
    • H04M1/675Preventing unauthorised calls from a telephone set by electronic means the user being required to insert a coded card, e.g. a smart card carrying an integrated circuit chip
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M15/00Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M17/00Prepayment of wireline communication systems, wireless communication systems or telephone systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M3/00Automatic or semi-automatic exchanges
    • H04M3/38Graded-service arrangements, i.e. some subscribers prevented from establishing certain connections
    • H04M3/382Graded-service arrangements, i.e. some subscribers prevented from establishing certain connections using authorisation codes or passwords
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M3/00Automatic or semi-automatic exchanges
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M7/00Arrangements for interconnection between switching centres
    • H04M7/12Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal

Definitions

  • This invention relates to a method and apparatus for communications with electromagnetic waves.
  • the system preferably operates at millimeter-wave frequencies and uses polarization diversity.
  • the information transmission capacity of a communications system can be substantially increased with the use of polarization diversity. This is true for both one-way and two-way communications systems. Vertical and horizontal polarizations are often used in satellite communications and other point-to-point microwave links to isolate both transmit and receive signals, or to increase information capacity.
  • a circularly polarized plane or quasi-plane electromagnetic wave propagating in open space may have its field vectors revolving clockwise (CP), or counterclockwise (CCP).
  • CP clockwise
  • CCP counterclockwise
  • Two such waves, rotating oppositely with respect to each other, are orthogonal to each other and may be isolated with proper antenna feeds and electronic circuitry.
  • precipitation and/or reflection/diffraction from buildings and other obstacles can distort the waves and cause elliptical polarization. If the waves become excessively elliptically polarized, the information carried by the waves cannot be retrieved.
  • U.S. Pat. No. 4,747,160 teaches a low power multi-function cellular television system capable of two-way communication services.
  • An omnidirectional transmitter transmits vertical and horizontal linear polarized waves.
  • the system taught by the '160 patent preferably operates in the 27.5 GHz to 29.5 GHz millimeter wave band.
  • U.S. Pat. No. 4,264,908 teaches a polarization correction network that automatically compensates for cross polarization caused by, for example, precipitation.
  • the network transmits vertical and horizontal linearly polarized waves.
  • U.S. Pat. No. 4,106,015 discloses a radar system that eliminates rain echo signals. Pulsed, polarized waves are transmitted, and two separate receiving channels receive orthogonal components of a rain echo signal. The rain echo signal is eliminated by adjusting an amplitude of the orthogonal components of the rain echo signal, and then adjusting the phase of the signals to be opposite with respect to each other.
  • U.S. Pat. No. 4,737,793 discloses a dual-polarized microstrip antenna capable of simultaneously transmitting mutually orthogonal polarizations, including clockwise and counterclockwise circularly polarized waves, to double the capacity of a given frequency band.
  • U.S. Pat. No. 4,146,893 teaches a satellite communications system which compensates for polarization distortion caused by precipitation and incomplete polarization characteristics of antennas by predistorting a circularly polarized wave to an elliptically polarized wave. As the elliptically polarized wave encounters the depolarizing medium, a circular wave forms and is received by the satellite.
  • U.S. Pat. No. 3,956,699 discloses an electromagnetic wave communications system which transmits and receives waves having mutually orthogonal polarizations. The system provides polarization control prior to power amplification when transmitting, and subsequent to amplification when receiving.
  • U.S. Pat. No. 5,337,058 teaches a fast switching lens which is positioned in front of a radar antenna to manipulate the polarization of a transmitted wave to various polarizations.
  • the lens can also receive waves of various polarizations.
  • U.S. Pat. No. 4,329,687 discloses a radar system which alternately radiates clockwise and counterclockwise circularly or elliptically polarized waves.
  • a relatively high signal-to-clutter ratio is achieved by analyzing the phase differences between the two orthogonal components of the transmitted wave and the phase differences of the two orthogonal components of the received wave.
  • elliptically and/or circularly polarized waves are simultaneously broadcasted from a transmitting antenna.
  • a first wave rotates in a direction opposite with respect to a second rotating wave.
  • precipitation such as rain, snow, or fog
  • diffraction/reflection due to urban obstacles, such as buildings can attenuate and depolarize such waves. Consequently, circularly polarized waves can become elliptical, and the axes of the elliptical waves can rotate. Without proper signal isolation features, the information carried by such distorted waves can be irretrievable.
  • the communications system includes an adaptive receiver capable of restoring circular polarization to such elliptically polarized waves.
  • the adaptive receiver includes an electromechanically driven antenna with an orthogonal-mode feed that receives the dual rotating waves. Components of each of the waves enter each of two channels. The frequency of the signals in the channels can be down-converted to an intermediate frequency (IF). If the received waves are elliptical, at any given time, the signals in the channel corresponding to the feed aligned with the major axis of the counter-rotating waves will have a greater magnitude than the signals in the channel corresponding to the feed aligned with the minor axis of the waves.
  • IF intermediate frequency
  • Each channel preferably has automatic gain control circuitry to equalize the magnitude of the signals in the channels. Portions of the signals in each channel undergo a phase shift of ⁇ 90° and are combined with the signals of the other channel to isolate one rotating signal from the other rotating signal.
  • a phase detector can detect the loss of quadrature between the two channels and emit a signal to a servomotor that rotates the orthogonal-mode feed of the antenna to align the feed with the major and minor axes of the signals.
  • an antenna diversity control switch controls a plurality of antennas to track the incident signal.
  • the diversity control switch samples the signal strength in each channel during the IF stage, and selects an antenna with sufficient signal intensity. Because the feeds of the selected antenna may not be precisely aligned with the major and minor axes of the rotating signals, an electronic phase shifter can provide quadrature control between the signals in the two channels.
  • Automatic gain control amplifiers can restore the signals in the channels to circular polarization, if necessary.
  • the first rotating signal can be isolated from the second rotating signal by phase shifting a portion of each signal and recombining the phase-shifted portion with the other signal.
  • the two isolated signals can be demodulated according to the modulation method used by the transmitter.
  • Local oscillator tracking can be incorporated at the IF stage with the use of proper filtering and phase-lock loop circuitry.
  • the use of a plurality of antennas and a diversity switch eliminates moving components, and is particularly suitable for implementation with monolithic integrated circuits. Such preferred embodiment is especially suited where compactness and/or low power consumption are desired.
  • a control center of a communications system transmits two circularly or elliptically polarized waves over a substantial azimuthal area to a number of subscribers, each having a transceiver to receive the signals.
  • the transceiver antenna is relatively highly directional, and thus can be relatively small.
  • the subscriber can transmit a return signal back to the control center. Because the antenna is relatively highly directional, substantial directive gain can be achieved so that relatively minimal power is required to transmit the signal to the control center.
  • the return signal can be used by the control center to select certain programming, or to adjust the power level of the transmission of the control center to compensate for fading caused by precipitation and/or obstacles.
  • FIG. 1 is a diagrammatic view of a point-to-multi-point broadcast system according to one preferred embodiment of this invention
  • FIG. 2 is a block diagram of a transceiver according to one preferred embodiment of this invention.
  • FIG. 3 is a schematic diagram of a portion of a transceiver according to one preferred embodiment of this invention.
  • FIG. 4 is a schematic diagram of a portion of a transceiver according to another preferred embodiment of 15 this invention.
  • millimeter waves and millimeter-wave frequencies refer to relatively high frequency electromagnetic radiation, particularly frequencies over about 18 GHz.
  • An electromagnetic communications system that uses dual polarization for signal transmission can effectively double the capacity of a channel.
  • cross-polarization and fading effects due to precipitation constrain two-way communications that use such polarization diversity.
  • rain, snow, or fog can attenuate and/or depolarize such waves.
  • buildings, trees, and other obstacles can also attenuate and/or depolarize such millimeter waves. These effects are particularly noticeable when a line-of-sight link is unavailable.
  • the method and apparatus for communications with electromagnetic waves according to this invention include signal restoration and isolation circuitry that achieve a communications system that can effectively operate in the millimeter-wave frequencies with polarization diversity in an urban environment.
  • the method and apparatus according to this invention achieve such a communications system in the millimeter-waveband with considerable cost effectiveness.
  • FIG. 1 shows a diagrammatic view of a point-to-multi-point two-way broadcasting system according to one preferred embodiment of this invention.
  • Control center 20 preferably simultaneously broadcasts two circularly or elliptically polarized waves rotating oppositely with respect to one another. If the depolarization effect of the medium is not severe, a combination of linear and circular/elliptical polarization can be used. According to another preferred embodiment of this invention, a single rotating circularly polarized wave provides sufficient channel capacity, and control center 20 transmits only one circular/elliptical polarized wave.
  • Control center 20 can transmit multi-channel programs having a variety of contents and signal formats to subscriber 22 and/or subscriber 24. Control center 20 can also receive return signals from subscriber 22 and/or subscriber 24 and perform switching and allocation of available channels according to the needs of subscriber 22 and/or subscriber 24.
  • Control center 20 preferably comprises an antenna that has substantial diversity in its radiation pattern, particularly with respect to azimuthal coverage. Although complete circular polarization in all directions may not be possible, elliptical polarization with relatively moderate eccentricity over a substantial area of distribution is feasible.
  • Precipitation zone 30, building 26 and building 28 may modify the polarization of the signals in two-way path 32 and/or two-way path 34. If the eccentricity in the ellipse prescribed by the field vector is not substantial, for example less than about 0.97, the two rotating signals in each of two-way path 32 and two-way path 34 can be discriminated with the receiver according to this invention. In relatively extreme circumstances, each rotating signal can approach linear polarization along the same direction as a result of reflection at an angle of incidence close to the Brewster angle. In such circumstances, an alternative signal path can be chosen, or, if no alternative signal path is available, an additional control center 20 or a relay station can be installed.
  • the method and apparatus for electromagnetic communications according to this invention differs from conventional cellular distribution systems.
  • Such conventional systems use a regular cell pattern with a fixed cell area to cover a subscription area.
  • control center 20 may have more than one antenna.
  • separate antennas that are aligned for optimal overlap in coverage are used to transmit and receive, respectively.
  • combiner 46 can accept signals from antenna 41 and transmitter 42 simultaneously. Controller 50 preferably coordinates the functions of the receiver or transceiver, and can provide allocation of channels or other services. Because all feed elements have finite signal isolation, a portion of the signal from transmitter 42 is preferably injected into signal isolator 48 for proper signal cancellation so that the receiver sensitivity can be maintained close to its intrinsic value. Additional signal isolation can be achieved by dedicating specific channels for receive only, and through the use of filter networks and synchronous detection. Demodulator 40 and modulator 44 can use spread spectrum modulation techniques, or any other modulation techniques known to those skilled in the art, to further increase channel capacity and signal isolation.
  • subscriber 22 and/or subscriber 24 use a highly directional antenna.
  • beam widths such as -3 dB, smaller than about 5° can be achieved with an antenna that has a diameter less than about 12 inches, at about 28 GHz frequencies.
  • Such an antenna generally eliminates fading due to multi-path propagation.
  • a return signal from subscriber 22 to control center 20 can be transmitted by retracing the signal transmitted from control center 20 to subscriber 22.
  • the reciprocal nature of the forward-backward wave propagation process ensures the preservation of the sense of polarization between the signals, and guarantees a return path to control center 20 if subscriber 22 has sufficient power. Because the antenna of subscriber 22 is highly directive, substantial directive gain can be achieved so that the power required for the signal from subscriber 22 to control center 20 can be less than 100 milliwatts, and thus within the range of solid-state amplifiers.
  • control center 20 can use the return signal from subscriber 22 to adjust the power level of the transmitter to compensate for fading, if necessary.
  • Modulation and demodulation of a multi-channel signal can be achieved by an array of modulators and demodulators with frequency tracking capabilities.
  • FIG. 3 shows a schematic view of an adaptive receiver portion of a transceiver according to one preferred embodiment of this invention.
  • Antenna 41 can receive two waves rotating oppositely with respect to each other.
  • antenna 41 comprises an orthogonal-mode feed. Components of each of the two waves enter channel 56 and channel 58.
  • Oscillator 64 and mixers 60, 62 down-convert the frequencies of the signals in channels 56, 58 to an intermediate frequency (IF). If the signals in channel 56 and channel 58 have an equivalent magnitude, the signals are derived from circularly polarized waves.
  • IF intermediate frequency
  • Automatic gain control amp 66 and automatic gain control amp 68 are preferably electrically coupled with differential amplifier 73 through diodes 71, 70 respectively. Automatic gain control amps 66 and 68 preferably operate nearly identically with respect to each other, and thus can approximately equalize the magnitude of the signals in channels 56, 58.
  • Channels 56, 58 are preferably electrically coupled to phase detector 88 through limiter 84 and limiter 86.
  • Phase detector 88 emits a signal to motor 90 through amp 89 as a function of a phase difference between the signals in channel 56 and the signals in channel 58.
  • Motor 90 can be a servomotor that adjusts antenna 41 as a function of the signal from phase detector 88.
  • a quadrature relationship can be restored to the signals in channels 56, 58 by rotating the orthogonal-mode feeds of antenna 41 with the major and minor axes of the ellipses of the rotating signals.
  • the receiver isolates one of the rotating waves from one of the channels 56, 58, and the other rotating wave from the other of the channels 56, 58.
  • An example of how this is achieved is as follows.
  • the phase of vector jC leads the phase of vector C by 90°.
  • the phase of vector -jD lags the phase of vector D by 90°.
  • the C component of the first wave and the D component of the second wave are absorbed by the lead corresponding to channel 56.
  • the jC component of the first wave and the -jD component of the second wave are absorbed by the lead corresponding to channel 58.
  • Channel 58 after being down-converted to an IF, splits into a second channel designated by reference numeral 58', as shown by FIG. 3.
  • One-half of the signal comprising components jC and -jD will enter channel 58' and be phase shifted +90° by phase shifter 75.
  • the components of the signal from channel 58' entering power combiner 78 are -C and D.
  • Power combiner 78 combines the -C and D components from channel 58' with the C and D components in channel 56.
  • the C component from channel 56 and the -C component from channel 58' cancel one another, leaving only one signal in channel 56, which is the rotating wave designated as D.
  • the rotating wave designated as C is isolated in channel 58.
  • One half of the C and D components from channel 56 enter channel 56'.
  • Power combiner 80 combines the jC and jD components of channel 56' with the jC and -jD components of channel 58. The jD components from channel 56' cancel the -jD components from channel 58, leaving only the rotating wave designated as C in channel 58.
  • the isolated signals in channels 56, 58, following power combiners 78, 80, are independent and can be demodulated according to the modulation method used by control center 20.
  • Filter and PLL circuit 82 can be used for tracking local oscillator 64, and for synchronous demodulation if necessary.
  • FIG. 4 shows a schematic diagram of the receiver portion of a transceiver according to another preferred embodiment of this invention.
  • the receiver shown in FIG. 4 uses antenna diversity control 100 to select one of a plurality of antennas 41.
  • Power combiner 99 receives a portion of the signals from channel 56 and channel 58.
  • antenna diversity control selects a particular antenna 41 that provides sufficient signal intensity.
  • the quadrature control can be used to restore quadrature between the signals in channel 56 and the signals in channel 58.
  • multiplier 88 receives components of the signals in channels 56 and 58.
  • the output signal of multiplier 88 is fed to electronic phase shifter 104 through amplifier 89.
  • Electronic phase shifter 104 restores the quadrature relationship between the signals in channel 56 and the signals in channel 58.
  • a pair of quadrature controls such as a pair of electronic phase shifters, can be used to restore quadrature.
  • the receiver shown in FIG. 4 requires no moving parts. This is particularly suited for applications where compactness and/or low power consumption are important factors. Such a design can be implemented with monolithic integrated circuits.
  • Intermediate frequency amplifiers 65, 67 can increase the magnitude of the signals in channels 56, 58.
  • the signals in channels 56, 58 can be restored to circular polarization by automatic gain control amplifiers 66, 68.
  • the rotating waves can be isolated from each other with phase shifters 75, 76 and power combiners 78, 80.
  • Power dividers 92, 94 can provide a portion of the signals in channels 56, 58 to filter and PLL circuit 82 for tracking of local oscillator 64, and synchronous demodulation.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Business, Economics & Management (AREA)
  • Computer Security & Cryptography (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Accounting & Taxation (AREA)
  • Strategic Management (AREA)
  • General Business, Economics & Management (AREA)
  • Theoretical Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Radio Transmission System (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Mobile Radio Communication Systems (AREA)
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  • Near-Field Transmission Systems (AREA)
  • Telephonic Communication Services (AREA)
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US08/420,372 1995-04-07 1995-04-07 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception Expired - Fee Related US5701591A (en)

Priority Applications (27)

Application Number Priority Date Filing Date Title
US08/420,372 US5701591A (en) 1995-04-07 1995-04-07 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
US08/612,320 US5764742A (en) 1995-04-07 1996-03-07 System for accessing telephonic communications and for conducting telephonic transactions
RO97-01849A RO120442B1 (ro) 1995-04-07 1996-04-05 Metodă şi sistem de comunicaţie prin unde electromagnetice
EE9700260A EE9700260A (et) 1995-04-07 1996-04-05 Multifunktsionaalne interaktiivne kommunikatsioonisüsteem ring-/elliptiliselt polariseeritud signaali edastamise ja vastuvõtmisega
KR1019970707092A KR19980703692A (ko) 1995-04-07 1996-04-05 원형 및 타원형의 편파 신호 전송부 및 수신부를 갖는다기능 상호작동형 통신 시스템
EP96912582A EP0864209A1 (en) 1995-04-07 1996-04-05 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
CA002217686A CA2217686C (en) 1995-04-07 1996-04-05 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
EA199700309A EA000444B1 (ru) 1995-04-07 1996-04-05 Способ многофункциональной интерактивной связи с передачей и приёмом сигналов с круговой/эллиптической поляризацией и система для его реализации
APAP/P/1997/001129A AP895A (en) 1995-04-07 1996-04-05 Multifunction interactive communications system with circularly/elliptically polarized signal transmission and reception.
CN96193755A CN1097363C (zh) 1995-04-07 1996-04-05 发送和接收圆形/椭圆极化信号的多功能交互通信系统
CZ973162A CZ316297A3 (cs) 1995-04-07 1996-04-05 Vícefunkční interaktivní spojovací systém s kruhově/elipticky polarizovaným vysílacím a příjmovým signálem
NZ306724A NZ306724A (en) 1995-04-07 1996-04-05 Reception of circularly polarised radio signals, system restores circular polarisation to signals distorted by reflection or rain
AU55355/96A AU713294B2 (en) 1995-04-07 1996-04-05 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
BR9604936-7A BR9604936A (pt) 1995-04-07 1996-04-05 Sistema de comunicação interativo multifuncional com transmissão e recepção de sinal polarizado de modo circular/elìptico
UA97115395A UA50736C2 (uk) 1995-04-07 1996-04-05 Багатофункціональна інтерактивна система зв'язку з круговою/еліптичною поляризацією сигналів прийому та передачі
GEAP19963974A GEP20012525B (en) 1995-04-07 1996-04-05 Multi-Functional Interactive Communications System with Circularly Elliptical Polarized Signal Transmission and Reception
JP8530496A JPH11503292A (ja) 1995-04-07 1996-04-05 円偏波信号・楕円偏波信号の送受信を行う多機能対話型通信システム
SK1359-97A SK135997A3 (en) 1995-04-07 1996-04-05 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
PCT/US1996/004694 WO1996031957A1 (en) 1995-04-07 1996-04-05 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
HU9801986A HU221392B1 (en) 1995-04-07 1996-04-05 Method and arrangement for the telecommunication by electromagnetic waves
TR97/01124T TR199701124T1 (xx) 1995-04-07 1996-04-05 Dairesel olarak elips �eklinde polarlanm�� sinyal g�nderimi ve al�m�n� haiz, �ok-i�levli interaktif ileti�im sistemi.
MXPA/A/1997/007733A MXPA97007733A (en) 1995-04-07 1997-10-07 System of multifunctional interactive communications with transmission and reception of signals circularly / in the form of eliptic polariz
NO974638A NO974638L (no) 1995-04-07 1997-10-07 Flerfunksjons interaktivt kommunikasjonssystem med sirkulært/elliptisk polarisert signalutsendelse og mottaking
OA70100A OA10623A (fr) 1995-04-07 1997-10-07 Système de communications interactives multifonction avec transmission et réception de signaux polarisés de façon circulaire/elliptique
US08/949,478 US6006070A (en) 1995-04-07 1997-10-14 Multi-function interactive communications system with circularly/elliptically polarized signal transmission and reception
BG102030A BG102030A (en) 1995-04-07 1997-11-06 Multifunctional interactive communication system having a circular'eliptic polarizing transmission and reception signal
PL96322656A PL180089B1 (pl) 1995-04-07 1997-11-06 Sposób i urzadzenie do lacznosci przy uzyciu fal elektromagnetycznych PL PL PL PL PL PL PL PL PL PL PL

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EP (1) EP0864209A1 (cs)
JP (1) JPH11503292A (cs)
KR (1) KR19980703692A (cs)
CN (1) CN1097363C (cs)
AP (1) AP895A (cs)
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CA (1) CA2217686C (cs)
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